I can't even recall if it was a movie or not. I know it involved a red headed girl who became the size of insects and proceeded to make friends and enemies at that size. If I recall correctly it ended with the girl going back to regular size and it then became live action.

I believe her enemy was a wasp.

I want to say her name is Katie or Katy, but I might be fabricating that.

Came out in the 80's possibly mid to late 70's.

All help or clarification is much appreciated.

I think I know the movie you are talking about because I vaguely remember it from my childhood. For some reason the name Penelope comes to mind, but I'm still searching the web for it. If it's the same show/movie, I seem to remember a kangaroo and the girl hopping down the sink when she shrinks. I'll keep looking.

Dot and the Kangaroo!

Very good! I've been wondering about this one for a while too.